# Pots & Planters

A container's material and porosity, not its price, decide how often a plant needs watering and whether it survives frost and sun outdoors; its form factor decides which spec actually applies, since a hanging basket's mounting rating, a grow bag's breathable fabric, and a raised bed's wood safety are each a different expert question.

## How it works

A pot or planter holds growing medium and roots while solving two opposing jobs: shedding excess water so roots get oxygen, and keeping enough moisture and structure to survive its environment. Porous walls - unglazed terracotta, concrete or hypertufa, and breathable fabric - let water evaporate out, drying the root zone faster and needing a dense, well-fired (vitrified) body, or for fabric no rigid wall at all, to survive repeated outdoor freezing without cracking. Non-porous plastic, resin, glazed ceramic and metal hold moisture longer and dry slower, but trap more solar heat when dark-colored and can water-log roots without enough drainage holes. Self-watering planters add a reservoir below an air gap; roots wick water up by capillary action instead of waiting on the surface. Hanging and rail-mounted planters turn the problem from drainage into load: wet soil can outweigh what the mounting hardware was rated for.

## How an expert narrows the choice

```mermaid
timeline
  section 1 · Form factor
    hanging_basket / rail_or_window_box : ask Mounting hardware and weight rating : skip Wood treatment and edible-garden safety
    fabric_grow_bag : ask Porosity and watering frequency : skip Frost hardiness, UV stabilization, Mounting hardware and weight rating, Self-watering (sub-irrigation) mechanism, Wood treatment and edible-garden safety
    self_watering_planter : ask Self-watering (sub-irrigation) mechanism : skip Drainage
    raised_garden_bed : ask Wood treatment and edible-garden safety : skip Mounting hardware and weight rating, Self-watering (sub-irrigation) mechanism, Container color and heat absorption, Height-to-diameter ratio
    ground_or_patio_pot : ask Drainage, Frost hardiness, Weight and portability : skip Mounting hardware and weight rating, Wood treatment and edible-garden safety
  section 2 · Indoor or outdoor use
    indoor : ask Saucer or drainage tray : skip Frost hardiness, UV stabilization
    outdoor_covered_patio : ask Frost hardiness : skip UV stabilization
    outdoor_exposed : ask Frost hardiness, UV stabilization
  section 3 · Material
    unglazed_terracotta / concrete_or_hypertufa : ask Frost hardiness, Porosity and watering frequency
    glazed_ceramic : ask Frost hardiness
    plastic_resin / fiberglass : ask UV stabilization, Container color and heat absorption, Frost hardiness
    wood : ask Wood treatment and edible-garden safety
    fabric_breathable : ask Porosity and watering frequency : skip Frost hardiness, UV stabilization
    metal : ask Container color and heat absorption
    biodegradable_paper_or_peat : ask Porosity and watering frequency : skip Frost hardiness, UV stabilization
```

1. **Form factor.** Ground pot, hanging basket, grow bag, self-watering, or raised bed?
   Each form factor has its own expert spec: a hanging basket's mounting rating, a grow bag's breathable fabric, a self-watering planter's reservoir, a raised bed's depth and wood safety. This fork decides which facet set applies.
   If hanging_basket or rail_or_window_box: ask Mounting hardware and weight rating; skip Wood treatment and edible-garden safety.
   If fabric_grow_bag: ask Porosity and watering frequency; skip Frost hardiness, UV stabilization, Mounting hardware and weight rating, Self-watering (sub-irrigation) mechanism, Wood treatment and edible-garden safety.
   If self_watering_planter: ask Self-watering (sub-irrigation) mechanism; skip Drainage.
   If raised_garden_bed: ask Wood treatment and edible-garden safety; skip Mounting hardware and weight rating, Self-watering (sub-irrigation) mechanism, Container color and heat absorption, Height-to-diameter ratio.
   If ground_or_patio_pot: ask Drainage, Frost hardiness, Weight and portability; skip Mounting hardware and weight rating, Wood treatment and edible-garden safety.
   Skip if already known: a query that already names 'grow bag', 'hanging basket', 'window box', 'self-watering', or 'raised bed', an earlier answer naming a mounting bracket or a reservoir.

2. **Indoor or outdoor use.** Indoors, a covered patio, or fully outdoors?
   Indoor pots never face frost or UV breakdown and need a saucer to protect floors; fully outdoor ones must survive both.
   If indoor: ask Saucer or drainage tray; skip Frost hardiness, UV stabilization.
   If outdoor_covered_patio: ask Frost hardiness; skip UV stabilization.
   If outdoor_exposed: ask Frost hardiness, UV stabilization.
   Skip if already known: a query that already says 'indoor plant', 'patio', or 'outdoor garden', an earlier answer naming a room or a climate zone.

3. **Material.** Terracotta, glazed ceramic, plastic, metal, wood, or fabric?
   Material sets the trade-off between how fast it dries out and whether it survives frost or sun; it decides which spec below even applies.
   If unglazed_terracotta or concrete_or_hypertufa: ask Frost hardiness, Porosity and watering frequency.
   If glazed_ceramic: ask Frost hardiness.
   If plastic_resin or fiberglass: ask UV stabilization, Container color and heat absorption, Frost hardiness.
   If wood: ask Wood treatment and edible-garden safety.
   If fabric_breathable: ask Porosity and watering frequency; skip Frost hardiness, UV stabilization.
   If metal: ask Container color and heat absorption.
   If biodegradable_paper_or_peat: ask Porosity and watering frequency; skip Frost hardiness, UV stabilization.
   Skip if already known: a query naming a material directly ('terracotta', 'plastic planter', 'fabric grow bag'), an earlier answer about watering frequency or frost risk.

## What to surface

### Form factor

Which physical form the container takes: a ground-standing pot, a hanging basket, a rail- or window-mounted box, a breathable fabric grow bag, a self-watering (sub-irrigated) planter, or a raised garden bed. It decides the entire spec set that follows: a hanging basket needs a rated mounting bracket, a grow bag needs breathable fabric, a self-watering planter needs a working reservoir, and a raised bed needs safe wood. Asking this first avoids asking about frost-proofing on a fabric bag or a mounting bracket on a raised bed. [4]

Values: ground_or_patio_pot, hanging_basket, rail_or_window_box, fabric_grow_bag, self_watering_planter, raised_garden_bed.
Question to ask: Ground pot, hanging basket, grow bag, self-watering, or raised bed?

Used as: top-level split, filter. Data: derived from listing fields, backfill cost low. Look for it as: Derive from the product title and category breadcrumb ('planter', 'hanging basket', 'window box', 'grow bag', 'self-watering', 'raised bed kit').
Title keyword match covers nearly every listing; default to ground_or_patio_pot when the title names no other form.

### Indoor or outdoor use

Whether the container will live indoors, on a covered patio, or fully exposed outdoors. Outdoor-exposed containers must survive rain, sun and, in cold climates, freeze-thaw cycles that indoor pots never face; indoor pots instead need a saucer or tray so overflow doesn't damage floors. [1] [4]

Values: indoor, outdoor_covered_patio, outdoor_exposed.
Question to ask: Indoors, a covered patio, or fully outdoors?

Used as: top-level split, filter. Data: derived from listing fields, backfill cost low. Look for it as: Often implied by category ('indoor planter' vs 'outdoor planter') rather than a stated field; garden-center patio pots default to outdoor_exposed.
Keyword-match title and category; default houseplant pots to indoor, garden-center patio pots to outdoor_exposed.

### Material

What the container is made of: unglazed terracotta, glazed ceramic, plastic or resin, fiberglass, concrete or hypertufa, metal, wood, breathable fabric, or biodegradable paper/peat. Material sets how fast the growing medium dries out (porous materials breathe, non-porous ones hold water longer) and whether the container itself can survive sun and frost outdoors, which decides almost every other spec that follows. [1] [2] [3]

Values: unglazed_terracotta, glazed_ceramic, plastic_resin, fiberglass, concrete_or_hypertufa, metal, wood, fabric_breathable, biodegradable_paper_or_peat.
Question to ask: Terracotta, glazed ceramic, plastic, metal, wood, or fabric?

Used as: top-level split, filter, shown on the card. Data: on the listing, backfill cost low. Look for it as: Almost always stated in the title or a 'material' attribute ('Terracotta Planter', 'Fabric Grow Bag', 'Galvanized Steel Planter').
Title keyword match; default to plastic_resin when unstated, since it is the most common material in mass retail.
Chart: position on a porosity/drying-speed axis, fabric and unglazed terracotta driest, glazed and plastic slowest.

### Drainage

How excess water leaves the container: pre-drilled holes, no holes (drill required or used as a cachepot liner), a built-in attached saucer, or a reservoir-based self-watering system. Roots that sit in waterlogged soil suffocate from lack of oxygen; a pot with no drainage holes is only safe for a live plant if it's used as a decorative outer cachepot over an inner pot that does drain. [1]

Values: pre_drilled_holes, no_holes_drill_required, no_holes_cachepot_use, built_in_attached_saucer, reservoir_system.
Question to ask: Does it already have drainage holes?

Used as: filter, shown on the card. Data: needs research, backfill cost medium. Look for it as: Usually stated as a bullet ('drainage hole included') or visible in product photos; decorative ceramic often omits it and should be checked.
Title/bullet keyword match catches most; photo inspection is needed for decorative ceramic listings that don't state it, so confidence is lower there.

### Volume capacity

How much growing medium the container holds, usually given in liters or gallons. Root volume limits plant size directly; nursery trade sizing (a '#1' or '1-gallon' container class) is a trade-class range, not a literal gallon, so two pots both labeled '#1' can differ in actual volume. [1] [5]

Range: 0.1 to 415 liters.
Question to ask: About how many liters or gallons of soil does it hold?

Used as: filter, sortable. Data: on the listing, backfill cost low. Look for it as: Usually stated directly ('10 Gallon Planter') but check whether the number is a trade-class size or an actual measured volume.
Parse the stated gallon/liter number from the title; flag trade-class ambiguity rather than treating the number as exact.
Chart: position on a size scale from small tabletop pot to large patio planter or raised bed.

### Diameter or footprint

The container's top diameter (or length and width for a window box or raised bed), independent of its volume. Diameter and depth set how much root room and soil mass a plant gets; traditional pot-trade sizing names (like a tall, narrow 'long tom') still show up in modern catalogs for shape as much as size. [1] [5]

Range: 2.5 to 61 cm.
Question to ask: Roughly how wide across the top does it need to be?

Used as: filter. Data: on the listing, backfill cost low. Look for it as: Usually stated as a dimension in the title or spec table; large modern patio planters and raised beds run well above even this widened range.
Parse the stated dimension; range combines the traditional cast-pot table's small end with the ANSI standard's fabric-bag diameters (10-24in) at the large end; treat anything above it as a large patio or raised-bed size rather than an error.
Chart: position on a size scale.

### Porosity and watering frequency

Whether the material's walls are permeable to water (unglazed terracotta, concrete/hypertufa, breathable fabric) or sealed (glazed ceramic, plastic, resin, metal), which changes how fast the growing medium dries out between waterings. Clay pots are permeable, so water evaporates through the walls and the soil dries faster; glazed or plastic pots lose far less water to evaporation and, without drainage holes, can stay too wet for root health. [1] [2]

Values: porous_dries_fast, non_porous_retains_moisture.

Used as: shown on the card, filter. Data: derived from listing fields, backfill cost low. Look for it as: Not a listed field; derive from the material value (terracotta, concrete, fabric imply porous; glazed ceramic, plastic, metal imply non-porous).
Pure lookup table keyed off the material facet; no additional data needed.
Chart: position on a drying-speed axis.

### Frost hardiness

Whether the container itself can survive repeated freeze-thaw cycles outdoors without cracking, judged by how non-porous and fully-fired (vitrified) its body is, not by whether it has a glaze. A common buyer mistake is assuming any glazed ceramic pot is frost-proof; glazing does not seal out water, so a porous clay body underneath can still absorb water that freezes, expands and cracks the pot. Only a body fired near vitrification reliably survives freeze-thaw and salt exposure. [2] [1]

Values: frost_proof_vitrified_body, frost_resistant_claimed_untested, not_frost_safe_bring_indoors, not_applicable_flexible_material.
Question to ask: Does it need to come indoors, or can it freeze outside?

Used as: filter, shown on the card. Data: needs research, backfill cost medium. Look for it as: Sometimes stated as 'frost-proof' or 'frost-resistant' on ceramic/terracotta listings; plastic and resin rarely state it because cracking isn't the failure mode.
Keyword-match 'frost-proof'/'frost-resistant' claims for ceramic and concrete; treat an unstated claim as not_frost_safe for unglazed terracotta given the vitrification requirement, and as not_applicable for plastic/resin/fabric.

### Container color and heat absorption

Whether the container is a dark or light color, or a reflective metallic finish, which changes how much it heats the growing medium in direct sun. Dark-colored pots absorb more solar heat than light-colored ones of the same material, warming the root zone faster; in hot climates or full sun, that extra heat can stress roots, especially in a small pot with little soil mass to buffer the swing. [1]

Values: dark_colored, light_colored, reflective_or_metallic.
Question to ask: Will it sit in full sun, and is it dark colored?

Used as: shown on the card. Data: on the listing, backfill cost low. Look for it as: Visible in the product photo and often in a color/title field.
Classify by the stated color name; treat black, charcoal, and dark bronze as dark_colored.
Chart: position on a heat-absorption axis, dark highest.

### Height-to-diameter ratio

Whether the pot is tall and narrow (a traditional 'long tom'), a standard rounded shape, or low and wide, relative to its diameter. Gravity pulls water down faster through a tall pot than a low, wide one, so tall pots drain and dry sooner while low wide pots hold a wetter zone longer; roots need both water and oxygen, so staying too wet for too long risks suffocating them. [1]

Values: tall_narrow_long_tom, standard_proportioned, low_wide_shallow.
Question to ask: Tall and narrow, or short and wide?

Used as: shown on the card, filter. Data: derived from listing fields, backfill cost low. Look for it as: Compute from stated height and diameter when both are given; otherwise infer from product photos.
A height:diameter ratio above about 1.3 reads as tall_narrow, below about 0.7 as low_wide, in between as standard; the >1.3 cutoff tracks the traditional long tom's own proportions (3in diameter by 3.75-4in depth, a 1.25-1.33 ratio); the <0.7 cutoff is a reasonable symmetric choice, not independently sourced.
Chart: position on a drainage-speed axis, tall narrow fastest.

### Mounting hardware and weight rating

What the hanging basket or rail/window box comes with to hang or mount it (bracket, S-hook, chain, rail clamp) and whether that hardware states a weight rating. Soil holds several times its dry weight once watered, so a bracket or hook with no stated rating is a real failure risk for a hanging basket; this matters for hanging and rail-mounted forms specifically, not ground pots. [4]

Values: bracket_or_hook_with_rated_capacity, bracket_or_hook_no_stated_rating, rail_clamp_included, sold_without_hardware.
Question to ask: Does it come with a hanger or bracket, and a weight limit?

Used as: filter, shown on the card. Data: on the listing, backfill cost medium. Look for it as: Hardware inclusion is usually in the title/bullets ('with S-hook', 'chain included'); a weight rating is less often stated and may require checking the full description.
Keyword match for hardware inclusion; treat an unstated weight rating as bracket_or_hook_no_stated_rating rather than guessing a number.

### Weight and portability

How heavy the container itself is, and whether a buyer can realistically move it once filled with wet growing medium, as distinct from any hanging bracket's rated capacity. A heavier container resists tipping and is more stable outdoors, but that same weight makes it hard to move once filled, which matters for anyone who needs to shift it onto a balcony or deck, or bring it in for winter. [6] [4]

Values: lightweight_easy_to_move, moderate_two_person_move, heavy_stable_hard_to_move.
Question to ask: Will you need to move it once it's filled with soil?

Used as: filter, shown on the card. Data: on the listing, backfill cost low. Look for it as: Empty/shipping weight is sometimes stated in the spec table; the trade-off mainly matters for ground/patio pots that might sit on a balcony or deck.
Treat large, heavy-bodied materials (concrete, glazed ceramic, unfilled large terracotta) with no stated weight as heavy_stable_hard_to_move by default, and lightweight plastic or fabric forms as lightweight_easy_to_move.
Chart: position on a weight/portability axis, light easiest to move.

### Saucer or drainage tray

Whether a matching saucer or tray is included, sold separately, or not applicable (outdoor in-ground use). Indoor pots need a saucer to catch drainage water and protect floors and furniture; an attached, non-removable saucer can be harder to empty after overwatering than a separate one. [1]

Values: attached_saucer, separate_saucer_included, sold_without_saucer, not_applicable_outdoor.
Question to ask: Does it come with a saucer or tray underneath?

Used as: filter. Data: on the listing, backfill cost low. Look for it as: Usually stated in the title or bullets ('with saucer', 'saucer sold separately').
Keyword match; default indoor pots with no mention to sold_without_saucer.

### Self-watering (sub-irrigation) mechanism

How a self-watering planter moves water from a reservoir up into the growing medium: a wicking chamber across an air gap, a capillary mat, or a simple water-level window with no wicking structure. A working sub-irrigated planter (SIP) needs an air gap between the water reservoir and the growing medium, not just a water-filled base, or roots sitting directly in standing water will rot instead of wicking it up as needed. [8] [4]

Values: wicking_chamber_with_aeration_gap, capillary_mat, water_level_window_no_wicking, none.

Used as: filter, shown on the card. Data: needs research, backfill cost high. Look for it as: Rarely detailed on listings beyond 'self-watering'; the aeration-gap design is usually only described on the brand's own site.
Needs a brand-page lookup per SKU; default unstated 'self-watering' claims to wicking_chamber_with_aeration_gap, the most common retail design, and flag for review.

### Wood treatment and edible-garden safety

Whether a wooden raised bed or planter is untreated/naturally rot-resistant wood, modern pressure-treated wood, legacy CCA (chromated copper arsenate)-treated wood, or a composite/plastic lumber. Older CCA-treated lumber can leach arsenic into soil and is restricted in the US and EU for residential use since 2004; a bed built from reclaimed or older CCA lumber should get a plastic liner between the wood and the soil, especially for edibles. [3] [7]

Values: untreated_or_rot_resistant, modern_pressure_treated, legacy_cca_treated, composite_or_plastic_lumber, metal_or_stone_no_wood.
Question to ask: Is the wood treated, and do you know with what?

Used as: filter, shown on the card. Data: needs research, backfill cost medium. Look for it as: New kits almost always state the wood species or 'cedar'/'pressure-treated'; CCA risk mainly applies to older or reclaimed lumber a buyer supplies themselves, not new retail kits.
New retail raised-bed kits made since 2004 are essentially never CCA-treated; flag this facet mainly for reclaimed/DIY wood, not for new kit listings.

### UV stabilization

Whether the plastic or resin is UV-stabilized to resist sun-driven fading, chalking and brittleness, versus a standard, untreated plastic. Untreated plastic left in full sun degrades: it fades, chalks and can turn brittle enough to crack within a couple of seasons, while UV-stabilized resin is formulated to resist that breakdown and is what durable outdoor planters are usually made from. [8]

Values: uv_stabilized, not_stated_or_untreated.

Used as: filter, shown on the card. Data: needs research, backfill cost medium. Look for it as: Sometimes called out as 'UV-resistant' or 'UV-stabilized resin' on durable outdoor planter listings; rarely stated on cheap mass-market plastic pots.
Keyword match 'UV' claims; treat budget unbranded plastic pots with no claim as not_stated_or_untreated rather than assuming protection.

## What you give up

- A porous pot breathes and dries out between waterings, which many plants prefer, but that same porosity means more frequent watering and, for rigid unglazed terracotta or concrete, a real risk of frost-cracking outdoors in winter unless the body is fired near vitrification. [1] [2] Board branch: "Breathes and dries fast, but needs more watering and frost care".

## Words you will meet

- **Terracotta**. Unglazed, porous fired clay; the traditional pot material, breathable but prone to frost-cracking unless fired near vitrification.
- **Vitrification**. Firing a clay body hot enough that it becomes dense and nearly glass-like, which is what actually makes a ceramic pot frost-safe, not the glaze.
- **Porosity**. How much a material's walls let water pass through; porous walls lose water to evaporation and dry the soil faster.
- **Trade gallon / container class**. A nursery sizing label like '#1' or '1-gallon' that marks a range of real volumes, not an exact gallon.
- **Sub-irrigated planter (SIP)**. The technical name for a self-watering planter that draws water up from a reservoir instead of being watered from the top.
- **Wicking**. Water moving upward through soil or a wick material by capillary action, from a reservoir into the root zone.
- **Aeration gap**. The air space a self-watering planter keeps between its water reservoir and the soil above, so roots don't sit directly in standing water.
- **Cachepot**. A decorative outer pot with no drainage hole, used to hide a plain inner pot that does drain.
- **Long tom**. A traditional name for a tall, narrow pot used for deep-rooting plants.
- **Hypertufa**. A lightweight, porous homemade-style concrete mix (cement, peat, perlite) used for rustic-looking planters.
- **Grow bag**. A soft-sided, breathable fabric planter that lets excess water evaporate through its sides rather than just through drainage holes.
- **CCA-treated lumber**. Wood pressure-treated with chromated copper arsenate, an older preservative restricted for residential use since 2004 because it can leach arsenic into soil.
- **UV-stabilized resin**. Plastic formulated with additives that slow sun-driven fading, chalking and cracking outdoors.

## Where we made a call

- Glazing a terracotta pot does not make it frost-proof; only a near-vitrified body reliably survives outdoor freeze-thaw cycles. (confidence medium). Sourced to the Terracotta Wikipedia article's materials-science section; no independent ceramics-industry source was reachable this run to add a second confirmation. [2]
- Dark-colored pots warm the root zone faster than light-colored pots of the same material and size. (confidence medium). Single-sourced to the Flowerpot Wikipedia article; a dedicated horticultural heat-stress study was not reachable this run. [1]
- A taller, narrower pot drains and dries faster than a low, wide pot of the same volume. (confidence medium). Single-sourced to the Flowerpot Wikipedia article's shape section; gravity pulls water down through more soil depth in a tall pot. [1]

## References

1. [Flowerpot](https://en.wikipedia.org/wiki/Flowerpot) (primer). Supports: Traditional cast-pot sizing: top diameter 1 to 20 inches, depth 2.5 to 18 inches; The tall, narrow 'long tom' pot shape is named and sized separately for deep-rooting plants; Nursery plastic pot sizes follow an ANSI standard; a '#1' container is a trade gallon, not a literal gallon; Clay pots are permeable, so water evaporates through the walls and dries soil faster; Glazed or plastic pots lose less water to evaporation and can stay too wet without drainage holes; Dark pots warm soil faster in sun than light-colored pots; Taller pots drain faster than low, wide pots because gravity pulls water down through more soil.
2. [Terracotta](https://en.wikipedia.org/wiki/Terracotta) (primer). Supports: Terracotta is not watertight; porousness decreases with surface burnishing and glazing can reduce but not eliminate permeability; A non-porous, near-vitrified clay body (not glazing alone) is necessary for terracotta to survive freeze-thaw cycles and salt exposure outdoors.
3. [Raised-bed gardening](https://en.wikipedia.org/wiki/Raised-bed_gardening) (primer). Supports: Raised beds are commonly built from lumber, but also metal, rock, concrete, plastic, or repurposed intermediate bulk containers (IBCs); CCA (chromated copper arsenate)-treated lumber, if used, should have a plastic liner between the wood and soil; CCA-treated lumber has been uncommon since 2004 in the US and EU due to regulatory restrictions.
4. [Container gardening](https://en.wikipedia.org/wiki/Container_gardening) (primer). Supports: Container types include pots, boxes, tubs, baskets, barrels, hanging baskets, window boxes, wall planters, and sub-irrigated planters (SIPs); Hanging baskets are suspended from ceilings, walls, or specially designed stands; window boxes fit on windowsills.
5. [American Standard for Nursery Stock (American Nursery & Landscape Association, 2004 ed.)](https://web.archive.org/web/2014/http://americanhort.org/documents/nursery_stock_standards_AmericanHort_2004.pdf) (standards body). Supports: Container classes (#SP1 through #100) are trade sizing classes, each covering a range of volumes; The smallest class #SP1 runs 6.5 to 8.0 cubic inches; the largest, #95/100, runs 20,790 to 25,410 cubic inches; The standard governs trade specifications only and does not apply to retail consumer transactions; Recommended fabric grow-bag diameters run from 10 to 24 inches across the standard's size table.
6. [Container Gardening (Knox County Master Gardeners, University of Illinois Extension, April 2011)](https://extension.illinois.edu/sites/default/files/container_gardening.pdf) (other). Supports: Dark colored or metal pots absorb heat which can damage roots; Heavier containers are more stable but can be hard to move onto balconies or decks; Porous pots and some types of plastic need protection from freezing temperatures.
7. [Chromated Arsenicals (CCA) - US EPA](https://www.epa.gov/ingredients-used-pesticide-products/chromated-arsenicals-cca) (regulator). Supports: Wood treated with chromated arsenicals was used in residential decks and playsets prior to 2004; Chromated arsenicals manufacturers voluntarily discontinued treated wood for homeowner uses in December 2003.
8. [EarthBox - How It Works](https://www.earthbox.com/how-it-works) (spec sheet). Supports: A sub-irrigated planter's core parts are a water reservoir, an aeration screen, wicking chambers, and an overflow drain; The aeration screen keeps an air gap between the reservoir and the growing medium above it; Wicking chambers draw water up from the reservoir into the growing medium by capillary action; The container is made of food-safe, UV-stabilized plastic to resist fading and wear.